As the transportation paradigm shifts from vehicle-oriented to pedestrian-oriented, active research has been conducted on road designs that consider the safety of pedestrians, cyclists, and personal mobility users. This study aims to respond to this change by developing installation warrant factors and improving the minimum size design standards for triangular islands. This study involved reviewing domestic and international laws and guidelines, analyzing the current installation status of triangular islands, examining case studies of improvements, and assessing policy changes. Based on the findings, important insights were derived, and improvement plans to enhance the safety of pedestrians, vulnerable users, and other road users were proposed. This study identified several issues and confirmed that policies in both domestic and international contexts are shifting towards minimizing or removing the triangular islands. Based on these findings, this study developed 24 factors for installation warrants to determine the installation of triangular islands, such as the design speed and peak-hour volume for pedestrians. In addition, the proposed improvements suggest increasing the minimum size design standards from 9m2 to 22m2 to ensure the safety of users. The factors of installation warrants and improved minimum size design standards proposed in this study are expected to help shift the operation of triangular islands from a vehicle-oriented to a pedestrian-oriented approach.
Mauremys reevesii (Reeves’ turtle) is an endemic freshwater turtle species found throughout East Asia. Due to a rapid population decline, the International Union for Conservation of Nature (IUCN) and the Korean government have classified this species as Endangered (EN). The reported largest population size of M. reevesii in the Republic of Korea was previously estimated to be approximately 20-30 individuals. Our study assessed the population size and structure of M. reevesii at Geumho Reservoir, Republic of Korea, using a capture-recapture data. A total of 433 M. reevesii were incidentally captured during a 35-week trapping process conducted from March to October 2023. The sex ratio of the captured population exhibited a male bias of 1.3 : 1. Sexual size dimorphism was observed only in body weight. Individuals were recaptured up to 11 times during the study period, with males and females being recaptured at an average of 2.1±2.0 times and 1.5±0.9 times, respectively. The estimated population size of M. reevesii in Geumho Reservoir was approximately 891 turtles. The absence of notable sexual size dimorphism and significant sex ratio differences suggests that the population in this area may have been established relatively recently. Compared to previous records, the population in Geumho Reservoir represents the largest single population of M. reevesii, both within the Republic of Korea and globally.
This study aimed to identify the selectivity of catches according to mesh size of gillnets, and to collect basic data for fisheries resource management plans for gillnets. The mesh selectivity test was conducted with five different mesh sizes (60, 66, 69, 75, and 96 mm) gillnet in coastal sea of Mukho port and the selectivity was analyzed using the Kitahara method. In results of the selectivity test, a total of 143 (36,249 g) of atka mackerel were caught and the 60 mm gillnet was the highest at 83 (18,596 g), which is about 58.0% of the total catch. The relative growth equation between body length and weight showed that weight tends to increase proportional to body length. The maximum length/mesh size value was showed 0.490 by the master curve of selectivity, and the 50% selection range was showed 0.138. Therefore, it was found that the size of the caught fish increased proportional to the mesh size. The results of this study were intended to be used as data for establishing a plan for efficient management of atka mackerel resources.
This study analyzes the visual image effects regarding the design changes of sleeves and shoulders on plus-size women in their 20s and 30s to propose ideas for plus-size women’s clothing production and design. Based on a plus-size women’s basic raglan sleeve shirt, six types of raglan sleeve shirts with various design elements were developed using a 3D virtual imaging program to analyze the visual image effect of each pattern’s features. The results showed that the A-shaped sleeve silhouette, exemplified by Pattern A2, makes the upper body look longer and slimmer as a whole. It also conveyed a sense of refinement and attractiveness, displaying positive effects regarding body shape and aesthetic perception. Meanwhile, O-shaped silhouettes, such as Pattern B1 and Pattern B2, showed positive effects regarding comfort and mobility, while Y-shaped silhouettes, such as Pattern C1 and Pattern C2, created a visually confident appearance. Furthermore, the research examined the effects of static images and dynamic videos on evaluation outcomes. The results showed that dynamic images enhanced immersion and vibrancy, thereby increasing focus on the apparel evaluated. The results of the visual image evaluation can be used as a basis for designing not only raglan sleeves but also overall sleeve shapes.
This study aims to prepare reference data that can be used to improve the size suitability of elderly men’s casual wear. The sizes of men aged 65–84 from the 8th Size Korea were analyzed and compared with those aged 45–54. First, as a result of classifying their body types according to Syzing systems for male adult’s garments (KS K 0050), more than 50% of the drop body types were “a protruding belly type (BB),” and more than 95% of the lower body types were “a thick waist type (B).” Additionally, elderly men with type BB or B were 3–5cm shorter in height, waist height, chest circumference, and hip circumference than middle-aged men. As there are currently only a few brands for elderly men, this means that the following problems may arise: If an elderly man wears a middle-aged man’s top based on his chest size, the chest and hip circumferences are adequate, but the length is insufficient, the waist circumference is insufficient, and the shoulder width is considered to be excessive. Similarly, pants designed to fit a waist size designation for middle-aged individuals will be larger than intended in terms of length, hip circumference, and thigh circumference.
The electronic structures of graphene nanoflakes (GNFs) were estimated for various shapes, sizes, symmetries, and edge configurations. The Hückel molecular orbital (HMO) method was employed as a convenient way of handling the variety of possible GNF structures, since its simplicity allows the rapid solution of large system problems, such as tailoring optoelectronic characteristics of molecule containing large number of carbon atoms. The HMO method yielded the electronic structures with respect to the energy state eigenvalues, with results comparable to those obtained by other approaches, such as the tightbinding method reported elsewhere. The analyses included the consideration of various types of edge configurations of 68 GNF systems grouped by their geometric shape, reflecting symmetry. It was inferred that GNFs in the small length scale regimes, below 1 nm, which are effectively small polycyclic aromatic hydrocarbon molecules, exhibit the optoelectronic characteristic of quantum dots. This is due to the widely spaced discrete energy states, together with large energy gaps between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). With increasing size this arrangement evolves into graphene-like ones, as revealed by the narrowing HOMO-LUMO gaps and decreasing energy differences between eigenstates. However, the changes in electronic structure are affected by the symmetries, which are related to the geometric shapes and edge configurations.
목적 : 본 연구에서는 노래의 템포(bpm) 및 데시벨(dB)에 따른 동공 크기 및 동적 조절 변화를 비교하고, 빛의 유무에 따른 차이도 비교해 보고자 한다. 방법 : 연구 대상은 안질환이나 시각 장애가 없는 성인 20명(남자 10명, 여자 10명, 평균연령 24.25±3.99세) 이었다. 완전 교정 상태에서 명소시에서 6 m 거리의 시표로, 암소시에는 무한대 거리로 측정하였다. 두 조건 모두 헤드셋을 착용하여 네 가지 음악 드럼(D), 메탈(M), 외국 팝(F), 클래식(C)을 들었을 때 동공 크기와 조절 반응의 변화를 각각 40 dB 미만, 60 dB 미만, 80 dB 이상으로 측정하여 비교하였다. 결과 : bpm 및 dB에 따른 자극이 있을 때, 유의한 차이를 보였다(p<0.010). 두 조건 모두 동일한 dB에서 bpm 이 달라졌을 때 자극량의 차이는 있었으나, bpm 변화에 따른 동공 크기와 동적 조절 변화량은 유의한 차이가 없었 다. 동공 크기와 동적 조절 변화량을 조도에 따라 비교했을 때, D 장르의 40 dB(p<0.050)과 F 장르의 60 dB (p<0.050)에서 동공 크기 변화량의 차이가 있었다. 조도가 없을 때 동적 조절 변화량이 더 증가하여, bpm과 dB에 따른 모든 그룹에서 유의한 차이가 나타났다(p<0.050). 결론 : 본 연구 결과, 각 노래의 bpm과 dB에 따른 동공 크기와 동적 조절 변화는 자극의 유무에 따라 영향을 받는 것으로 확인되었다. 특히, 암소시에서는 동적 조절 변화에 더 큰 영향을 미쳤으며, 명소시에서는 동공크기 변 화가 컸다.
목적 : 누진 가입도 안경 착용자의 안경테의 크기와 얼굴 형태에 적합한 안경테를 비교하여 안경테 크기와 신체 적(역학적) 불편감 사이의 연관성을 조사하였다. 방법 : 누진 가입도 안경 착용자 중 안경의 피팅 상태가 적절한 71명(남성 37명, 여성 34명, 평균 54.52±8.78 세)이 참여하였고, 신체적 불편감을 설문지로 조사하였다. 안경테 크기를 FHD(front horizontal dimension), FTB(front to bend), LOD(length of drop) 및 TL(temple length)로 확인하였다. 얼굴 형태를 계측한 후 얼굴에 적합한 안경테 크기를 계산하였고, 착용하고 있는 안경테 크기와 비교하였다. 결과 : 신체적 불편감의 정도는 관자놀이 눌림, 흘러내림, 코 눌림, 귀 눌림 순으로 높았으며, 불편함을 경험한 비율은 흘러내림, 코 눌림, 귀 눌림, 관자놀이 눌림 순으로 높았다. 착용한 안경테의 FHD는 남녀 모두 얼굴 계측 으로 계산한 안경테 설계값보다 작았다(p=0.001). 착용한 안경테의 FTB는 남녀 모두 안경테 설계값보다 작았으 며, 착용한 안경의 LOD는 설계값보다 컸고 여성은 남성보다 길었다(all, p=0.001). 결론 : 착용한 남녀 안경의 FHD는 얼굴 형태에 비해 작아 관자놀이 눌림의 원인이 될 수 있고, 측면부 LOD는 얼굴에 비해 커서 흘러내림과 코 눌림의 원인이 될 수 있다. 얼굴 형태에 적합한 안경테 크기를 선택할 수 있도록 안경테의 FHD와 측면부 전체 길이(FTB+LOD)가 여러 사이즈로 제작되어야 할 것이다.
자기공명영상 평가 시 정확한 영상평가를 방해하는 요인에는 여러 가지가 있다. 그중 측정자로 인한 관심 영역의 크기 설정도 여러 요인 중 하나인데, 아직 다른 요인에 비해 관심 영역의 크기 설정은 연구가 부족한 실정이다. 이에 본 연구에서는 관심 영역의 크기 변화에 따른 SNR의 변화를 통계적으로 비교·분석하여 설정하는 방법을 제시하고 그 유용성을 증명하고자 하였다. 연구 방법은 팬텀의 T1, T2 강조영상을 획득한 다음 획득한 영상에 관심 영역의 크기를 변화시켜 신호강도를 측정한 후 관심 영역의 크기 변화에 따른 SNR 산출하여 비교평가 하였다. 연구 결과 T1 강조영상은 관심 영역의 크기 설정 시 20% 이하, T2 강조영상은 40% 이하로 설정할 때 기준 관심 영역 크기와 SNR이 통계적으로 차이가 없었다. 결론적으로 관심 영역의 크기 설정 시 본 연구의 통계를 이용한 설정 방법을 적절히 활용하여 측정을 시행한다면 관심 영역 크기 설정의 합리적 근거를 마련할 수 있어 유용하리라 판단된다.
Ceramic materials have become essential due to their high durability, chemical stability, and excellent thermal stability in various advanced industries such as aerospace, automotive, and semiconductor. However, high-performance ceramic materials face limitations in commercialization due to the high cost of raw materials and complex manufacturing processes. Aluminum borate (Al₁₈B₄O₃₃) has emerged as a promising alternative due to its superior mechanical strength and thermal stability, despite its simple manufacturing process and low production cost. In this study, we propose a method for producing Al₁₈B₄O₃₃ spherical powder with increased uniformity and high flowability by controlling the particle size of B₂O₃. The content ratio of the manufactured Al18B4O33 spherical powder was Al2O3: B2O3 = 87:13, and it exhibited a 17% reduction in the Hausner ratio (1.04) and a 29% decrease in the angle of repose (23.9°) compared to pre-milling conditions, demonstrating excellent flowability.
This study compared and analyzed fish communities and mortality rates based on different survey methods (mesh size and retrieval frequency) of stationary nets, which are actively used in freshwater fish surveys in Korea, and proposed an appropriate survey method. Field surveys were conducted on the mainstream of the Nakdong River from May to June 2022 through a total of 10 times of fyke net surveys. The number of species and individuals collected varied significantly depending on the mesh size of the net (5 mm vs. 15 mm) (P<0.001), and larger species with an average total length of over 9 cm were mainly collected in the 15 mm mesh. However, the number of species (P=0.684) and individuals (P=0.100) collected did not show statistically significant differences depending on retrieval frequency (once/24 hours vs. twice/24 hours). In contrast, the mortality rate of fish differed based on all survey methods (mesh size, P<0.001; retrieval frequency, P<0.05), with mortality decreasing as the mesh size increased and retrieval frequency increased. Fyke nets are one of the standard fishing gears used in freshwater fish research in Korea, and to ensure species diversity, it is recommended to maintain the current standard mesh size of 5 mm. However, reducing the current 48-hour deployment time or increasing the retrieval frequency could lower the mortality rate. Furthermore, future research should focus on the differences in fish communities based on the combination of fishing gears commonly used in Korea to improve fish survey methodologies suitable for domestic freshwater environments.
This study determined the minimum size of a representative molecular structure for use in future dynamic analyses of asphalt binders. The minimum representative size, considering factors such as aging, additive types, and temperature variations, was established using density and radial distribution functions. This approach ensures that the structure reflects temperature-dependent property changes, which are critical characteristics of asphalt binders. In this study, the structure of asphalt-binder molecules was generated using the composition proposed by Li and Greenfield (2014) for AAA1. To assess the appropriateness of the molecular structure size, we generated additional structures, X2 and X3, maintaining the same composition as X1, but with two and three times the number of molecules, respectively, as suggested by Li and Greenfield (2014). Silica and lignin were considered as additives, and the aging conditions examined included unaged, short-term aging, and long-term aging. In addition, 11 temperature conditions were investigated. The density and radial distribution functions were plotted and analyzed. The variables influencing the density and radial distribution functions were set as the aging degree of the asphalt binder (unaged, short-term aging, long-term aging), 11 temperature conditions ranging from 233 to 433 K in 20 K intervals, structure size (X1, X2, and X3), and the presence of additives (no additives, silica, and lignin). For density, clear differences were observed based on the degree of aging, temperature conditions, and presence of additives, whereas the structure size did not significantly affect the density. In terms of radial distribution functions, the X1 structure reflected differences based on the degree of aging and the presence of additives but was limited in exhibiting temperature-dependent variations. In contrast, the X3 structure effectively captured temperature-dependent trends, indicating that the size of the molecular structure is crucial when evaluating energy calculations or physical tensile strength, necessitating careful assessment.
This study aims to develop a detailed sizing system for lower body clothing for elderly obese women, using data from the 8th Korean Anthropometric Survey. The research targets 296 elderly women aged 60 to 85, selected from 805 participants in total, who meet the following criteria: Rohrer Index of 1.6 or above, Body Mass Index of 25 or higher, and Waist-Hip Ratio of 0.85 or greater. Elderly women with abdominal obesity exhibit shorter lower body proportions and greater fat accumulation in the torso, around the chest and waist. The findings show that women in their 60s have the highest level of obesity, while waist width and thickness are greatest in women in their 70s, suggesting that abdominal obesity increases with age. According to the KS standards, the main measurement categories were divided into 5cm increments for height, while waist and hip girth were categorized into 5cm and 3cm, respectively, to analyze the distribution of sections. Clothing size standards for lower garments that require a precise fit, such as skirts and formal pants, are presented in 13 sizes, corresponding to a waist girth range of 85–100cm and a hip girth range of 88–97cm. Detailed measurements are categorized into primary and reference areas. Additionally, sizes were presented differently based on whether a precise fit was necessary. For items that did not require a precise fit, ranges were indicated with letters, or ranges were indicated with measurements. Detailed sizes were categorized into primary and reference areas.
그래핀 산화물(GO), 폴리에틸렌 글리콜 다이아크릴레이트(PEGDA), 폴리에틸렌 글리콜 메틸 에터 아크릴레이트 (PEGMEA)의 나노복합체를 자외선 광중합을 통해 합성하였다. GO는 가교된 폴리에틸렌 옥사이드(XPEO) 매트릭스 내에 최 대 1.0 wt% 농도까지 균일하게 분산시켰다. 더 높은 농도에서는 GO가 응집되는 경향을 보였다. 잘 분산된 GO는 친수성 PEO 사슬과 추가적인 화학적 가교 네트워크를 형성했다. XPEO-GO 나노복합체는 GO 농도에 따라 기계적 강도 및 염과 가 스에 대한 차단 특성이 향상된 것으로 나타났다. 이 연구는 다양한 GO 농도와 플레이크 크기를 가진 XPEO-GO 하이드로겔 의 제조 및 특성화를 다루고 있다. 이러한 특성은 나노복합 하이드로겔이 강화된 XPEO 기반 바이오소재 및 고급 항균성 한 외여과(UF) 친수성 코팅에서의 잠재적 응용 가능성을 시사한다.